Function diesel::debug_query
source · [−]pub fn debug_query<DB, T>(query: &T) -> DebugQuery<'_, T, DB>
Expand description
Takes a query QueryFragment
expression as an argument and returns a type
that implements fmt::Display
and fmt::Debug
to show the query.
The Display
implementation will show the exact query being sent to the
server, with a comment showing the values of the bind parameters. The
Debug
implementation will include the same information in a more
structured form, and respects pretty printing.
Example
Returning SQL from a count statement:
let sql = debug_query::<DB, _>(&users.count()).to_string();
assert_eq!(sql, "SELECT COUNT(*) FROM `users` -- binds: []");
let query = users.find(1);
let debug = debug_query::<DB, _>(&query);
assert_eq!(debug.to_string(), "SELECT `users`.`id`, `users`.`name` FROM `users` \
WHERE `users`.`id` = ? -- binds: [1]");
let debug = format!("{:?}", debug);
let expected = "Query { \
sql: \"SELECT `users`.`id`, `users`.`name` FROM `users` WHERE \
`users`.`id` = ?\", \
binds: [1] \
}";
assert_eq!(debug, expected);